The 27-item Literacy of Suicide Scale (LOSS) is a test designed to measure the respondent’s suicide knowledge. The purpose of this study is to examine the psychometric properties of the Malay-translated version of the LOSS (M-LOSS) and its association to sociodemographic factors and mental health literacy. The 27-item LOSS was forward–backward translated into Malay, and the content and face validities were assessed. The version was distributed to 750 respondents across West Malaysia. Rasch model analysis was then conducted to assess the scale’s psychometric properties. The validated M-LOSS and the Malay version of the Mental Health Knowledge Schedule (MAKS-M) were then distributed to 867 respondents to evaluate their level of suicide literacy, mental health literacy, and their correlation. Upon Rasch analysis, 26 items were retained. The scale was found to be unidimensional, with generally satisfying separation and reliability indexes. Sex, socio-economic status, and experience in mental health were found to significantly impact the mean score for mental health literacy. This study also found a significant mean difference for suicide literacy across school types. Furthermore, while this study observed a weak but significant negative correlation between age and suicide literacy, no correlation was found between mental health and suicide literacy.

Parents, guardians, and teachers are the informal sources of mental health support that adolescents rely on. Nevertheless, limited mental health knowledge limits their ability and confidence in providing appropriate assistance. This study aims to (1) evaluate the relationship between the roles of parents/guardians and teachers and their responses to discover the common misconceptions on mental health among those providing informal support to adolescents and (2) determine which demographic factors would act as the strongest predictor influencing their mental health literacy (MHL) status. The cross-sectional study recruited 867 parents, guardians, and teachers of adolescents from 24 government secondary schools’ parent–teacher associations via multistage stratified random sampling. Parents, guardians, and teachers’ MHL were evaluated using the Mental Health Knowledge Schedule—Malay Version (MAKS-M). The collected data were analyzed using Pearson’s Chi-squared test to investigate the association between the respondents’ roles and responses. Multiple Regression analysis was used to determine the predictors of MHL. The score of MAKS-M for the current study sample is 73.03% (M = 43.82, SD = 4.07). Most respondents responded incorrectly on Items 1 (employment), 6 (help-seeking), 8 (stress), and 12 (grief). Teachers provided more favorable responses on several items than parents and guardians. Finally, younger age, higher income, knowing someone with mental disorders, and having experience of attending formal training on mental health first aid were the significant predictors of MHL. MHL interventions in Malaysia should cater to older adults of lower socioeconomic status and lesser experience in mental health, specifically highlighting the stigmas on mental health help-seeking behaviors, treatment, and employment concerns, plus the recognition of various mental health diagnoses.